Simplify code pattern of 'folio->index + folio_nr_pages(folio)' by using
the existing helper folio_next_index() in filemap_get_folios_contig().

Signed-off-by: Minjie Du <duminjie@vivo.com>
---
 mm/filemap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index 9710f43a89ac..ec8a3bbddab4 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2173,7 +2173,7 @@ unsigned filemap_get_folios_contig(struct address_space *mapping,
 
 	if (nr) {
 		folio = fbatch->folios[nr - 1];
-		*start = folio->index + folio_nr_pages(folio);
+		*start = folio_next_index(folio);
 	}
 out:
 	rcu_read_unlock();
-- 
2.39.0